• 한국환경보건학회지
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• 제26권4호
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• pp.141-147
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• 2000

Due to a rapid in automobiles since the 1980’s, the concentration of NO, and HC has also increased along with cases of VOCs. These air pollutants have created $O_3$ concentration, which cause a harmful effect to the human health. This issue has become a subject of great public interest. For this paper, to compare the concentration of $O_3$, NO, N $O_2$ between the rural and urban area in the winter, the concentrations of each have been measuredevery hour during Jan.~Feb. 2000, 1998, respectively. To calculate the Photochemical Steady State, $\Phi$= $J_{N O_2}$[N $O_2$]/ $k_1$[NO][ $O_3$], temperature and $J_{ N O_2}$ has been determined. The NO concentration in the rural are showed at below 10 ppb while the NO concentration in the urban area showed maximum value of 90~120 ppb. But the $O_3$ concentration in both areas showed less than 30 ppb. The reason is that the N $O_2$ photodissiciation rate is low due to the temperature being below 2$^{\circ}C$ and less than 60 degrees in the solar zenith angle during the winter time, which makes the $O_3$ concentration in both areas, similar in the concentration level. N $O_2$ photodissociation rate in both ares showed maximum value of 3.0mW/$\textrm{cm}^2$. Values of $\Phi$ determined from the rural area was consistently the unity, approaching 1. But values of $\Phi$ determined from the urban was roughly higher than unity, approaching above 1or 2 for clear sky-high sun(10:00~16:00).

• Asian Journal of Atmospheric Environment
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• 제6권3호
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• pp.147-168
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• 2012

Among all hazardous air pollutants, polycyclic aromatic hydrocarbons (PAHs) are more significant owing to their carcinogenic, mutagenic and teratogenic properties. Many researchers worldwide have focused on determining the concentrations of PAHs in ambient air. However, the literature survey reveals that the seriousness of air pollution in Asia in terms of PAHs, compared to the rest of the world. Owing to the importance of PAHs in Asia, this paper reviews the concentrations of PAHs in Asia in recent years. For convenience, this paper describes the concentrations of PAHs in developed Asian countries reported during 2000-2011 as Part-I and in developing Asian countries as Part-II. The first section of this review provides a brief description of the properties, sources of PAHs and the health effects caused by their presence in the atmosphere. The ambient air PAH concentrations in both particle and vapor phases in developed Asian countries are then discussed. This study finds the ambient air concentrations of PAHs in developed Asian countries was higher than the Western countries but was lower than the developing Asian countries. The present review predicts the accurate toxicity due to the presence of PAHs in the atmosphere by calculating the Risk Weighted Concentration (RWC), regardless of the total amount of PAHs. The total data obtained during the literature survey is tabulated and presented as supplementary information to the readers.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.7.1-7.9
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• 2013

Objectives We investigated the particle mass size distribution and chemical properties of air pollution particulate matter (PM) in the urban area and its capacity to induce cytotoxicity in human bronchial epithelial (BEAS-2B) cells. Methods To characterize the mass size distributions and chemical concentrations associated with urban PM, PM samples were collected by a 10-stage Micro-Orifice Uniform Deposit Impactor close to nearby traffic in an urban area from December 2007 to December 2009. PM samples for in vitro cytotoxicity testing were collected by a mini-volume air sampler with $PM_{10}$ and $PM_{2.5}$ inlets. Results The PM size distributions were bi-modal, peaking at 0.18 to 0.32 and 1.8 to $3.2{\mu}m$. The mass concentrations of the metals in fine particles (0.1 to $1.8{\mu}m$) accounted for 45.6 to 80.4% of the mass concentrations of metals in $PM_{10}$. The mass proportions of fine particles of the pollutants related to traffic emission, lead (80.4%), cadmium (69.0%), and chromium (63.8%) were higher than those of other metals. Iron was the dominant transition metal in the particles, accounting for 64.3% of the $PM_{10}$ mass in all the samples. We observed PM concentration-dependent cytotoxic effects on BEAS-2B cells. Conclusions We found that exposure to $PM_{2.5}$ and $PM_{10}$ from a nearby traffic area induced significant increases in protein expression of inflammatory cytokines (IL-6 and IL-8). The cell death rate and release of cytokines in response to the $PM_{2.5}$ treatment were higher than those with $PM_{10}$. The combined results support the hypothesis that ultrafine particles from vehicular sources can induce inflammatory responses related to environmental respiratory injury.

• 한국대기환경학회지
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• 제31권5호
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• pp.437-448
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• 2015

The purpose of this study is to present the source contribution of the fine particles ($PM_{2.5}$) in Chungju area using the CMB (chemical mass balance) method throughout the four seasons in Korea. The Chungju's annual average level of $PM_{2.5}$ was $48.2{\mu}g/m^3$, which exceeded two times higher than standard air quality. Among these particles, the soluble ionic compounds represent 54.2% of fine particle mass. Additionally, the OC concentration in Chungju stayed similar to other domestic cities, while the EC concentration decreased significantly compared to other domestic/international cities. The concentration of sulfur represented the highest composition (8%) among the fine particle compounds. According to the CMB results, the general trend of the $PM_{2.5}$ mass contributors was the following: secondary aerosols (50.5%: ammonium sulfate 26.5% and ammonium nitrate 24.0%) > gasoline vehicle (18.3%) > biomass burning (11.0%) > industrial boiler (6.0%) > diesel vehicles (4.4%). The contribution of the secondary aerosols was the main cause than others. This impact is assumed to be emitted from air pollutants of urban cities or neighbor countries such as China.

• 한국자동차공학회논문집
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• 제7권7호
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• pp.15-23
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• 1999

In recent years, environmental damage to urban area becomes serious problem due to the exhaust emissions by increasing the number of vehicle . Especially, diesel particulate matters(DPM) are hazardous air pollutant s to human health and environment. The reduction technologies of exhaust emissions from diesel engines are improvement of engine combustion, fuel quality and development of diesel exhaust aftertreatment. In this study, a diesel oxidation catalyst(DOC) that is one of diesel exhaust aftertreatments was made for performance evaluation . It was tested for NA and turbocharged engine by D-13 mode that currently be used for regulation driving test mode in Korea Scanning mobility particle sizer (SMPS) was used for the analysis of the particle size distribution with and w/o DOC. As the results , for NA and tubochartged engine, CO, THC, DPM was respectively reduced 85.7, 40.7,3.3% and 79.1, 53.1, 11.6% by DOC. Test results of particle size distribution was showed that particle number is 107 ~108per ㎤ , 2 $\times$105 ~5$\times$105$\mu\textrm{g}$/㎥ for weight concentration and 100~200nm for particle mean size in diesel engine and there is no effect to reduce the particle concentration by the DOC.

• 한국환경보건학회지
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• 제14권2호
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• pp.29-41
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• 1988

This study was performed to investigate the air pollution levels in Daegu area titrough measuring of contents of water, chlorophyll, water soluble sulfur and lead metal in the leaves of roadside trees and chemical properties of soil under the urban trees. The results can be summarized as follows 1. The range of water content was from 60.4% to 74.6%. The comparisons of chlorophyll, water soluble sulfur and water content were regression equation, chlorophyll=0.1981+ 0.0040 water content (July), water soluble sulfur=3,139-0.0416 water content (July). and correlation coefficient, r=0.561 and r=0.549 respectively 2. Average contents of chlorophyll, water soluble sulfur and lead metal in the leaves of roadside tree at sampling sites were chlorophyll 0.050, 0.072mg/cm$^2$, water soluble sulfur 0.244, 0.333%, and lead metal 12.25, 12.68ppm in Oct. and Jul. respectively. 3. Correlation between chlorophyll and contents of water soluble sulfur and lead metal in the leaves of roadside tree at sampling sites were water soluble sulfur r=-0.564, -0.613 and lead metal r=-0.693, -0.699 in October and July, respectively. 4. Correlation between chlorophyll and water content, water soluble sulfur and lead metal in the leaves of tree showed positive significance.

• 한국대기환경학회지
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• 제12권1호
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• pp.91-99
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• 1996

Ozone, sulfur dioxide, and nitrogen oxides were measured at Kosan, Cheju Island, Korea during the period of March 11 .sim. April 19, 1994. During the measurement period, the average SO$_{2}$ and NOx concentrations were about 0.97 ppb and 3.5 ppb, respectively. Average NO concentration was below the detection limit and thus the effect of NO during the period was negligible. The concentrations of SO$_{2}$ and Nox were lower than those at other urban area in Korea but higher than other remote areas in the world. Average $O_{3}$ concentration for the period was about 55 ppb, slightly higher than or comparable to those at remote marine areas in the world. Detailed analyses of trend of gaseous species concentrations show that the effects of local NO emission sources for NOx concentration were significant during the period, while those of local SO$_{2}$ emission sources were not high. Backward trajectory analysis results show that when SO$_{2}$ or $O_{3}$ concentration was higher than the average concentrations, the air parcels were transported from China.

• 한국환경보건학회지
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• 제38권6호
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• pp.472-481
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• 2012

Objectives: This study aims to investigate the AD (allergic diseases: asthma, allergic rhinitis and atopic dermatitis) prevalence among elementary schoolchildren in an industrial city, Ulsan, and identify major environmental risk factors associated with AD prevalence. Methods: Data on the physician-diagnosed prevalence over the past 12 months and potential risk factors of AD were collected through a questionnaire from a 2009-2010 survey of 4,067 schoolchildren living in different urban environments. The logistic regression analysis was performed to assess differences in AD prevalence among the areas and to determine which environmental factors impacted AD. Results: Our survey results showed that the AD prevalence rate ranged between 26.2% and 35.9%. Children living in polluted areas (near industrial and central urban areas) had about a 10% higher prevalence of AD than did those living in coastal or suburban residences. The Chi-Square test demonstrated that this local difference was statistically significant before and after adjustment of major confounders such as parental AD history and parental education. The results of the logistic regression analysis showed a statistically significant association between several environmental factors (ventilation in winter, odor conditions and exposure to traffic smoke, and outdoor $PM_{10}/O_3$ pollution) and the prevalence of AD found by multivariate model after adjusting confounders. Conclusion: These results suggest that local differences in AD prevalence are significantly associated with outdoor environmental factors. Although there are likely to be other risk factors for AD, living in a polluted area and exposure to high levels of air pollutants can contribute to an increased risk of childhood AD.

• 토지주택연구
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• 제6권4호
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• pp.231-237
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• 2015

본 연구는 다변화 되는 건설환경에서 모듈러 주택에 대한 관심이 높아지고 있어 모듈러 목업 주택을 대상으로 신축시 실내공기질 현황을 측정하였다. 붙박이 가구가 미설치된 세대(101호)와 붙박이 가구가 설치된 세대(102호), 2세대를 대상으로 시간경과에 따라 3차 측정을 실시하였다. 1차는 마감 및 붙박이 가구 설치 직후 측정하였으며 2차는 베이크아웃 실시 이후, 3차는 약 2.5개월(77일) 이후 측정하였다. 측정결과 1차 측정시 붙박이 가구 설치세대가 오염물질 방출농도가 높았으나 톨루엔의 경우를 제외하고 모두 권고기준 이하로 나타났다. 3차 측정시에는 톨루엔과 스티렌을 제외하고 두세대가 유사한 방출량으로 나타났으며 두세대 모두 미미한 수준으로 방출량이 낮아졌다. 이는 측정세대 모듈이 적어($14.7m^2$) 베이크아웃 및 환기에 의한 영향이 크게 나타난 것으로 판단되며 이를 통해 오염물질이 외부로 방출되어 저감된 것으로 판단된다. 일반 공동주택의 입주시점을 고려한다면 모듈러 주택의 경우도 모두 실내공기질 권고기준 이하로 나타날 것으로 판단되며, 가구에 의한 영향은 톨루엔이 가장 큰 영향을 받는 것으로 나타났다. 향후에는 모듈조합을 통해 중형 이상 규모 모듈러 주택에 있어서 가구설치 여부에 따른 상관관계를 살펴 볼 필요성이 있을 것으로 판단된다.

• Asian Journal of Atmospheric Environment
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• 제7권2호
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• pp.120-128
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• 2013

The concentration and composition of particulate matter (PM) in the atmosphere can directly reflect the environmental pollution. The atmospheric pollution in some Cameroonian cities is increasing with the industrial development and urbanization. Air pollution is inherently complex, containing PM of varied size and composition. This PM exists as a dynamic cloud interacting with sunlight and is modified by the meteorology. The reflectometer and the EDXRF spectrometry are applied to determine the concentration of some specific elements at four sites in the city of Yaound$\acute{e}$. The particular aim of the present work is to put in place data base on air pollution in urban area and elaborate regulations on the emissions issued to industrial and vehicle activities. This study provides an overview of the concentration of black carbon and some specific elements in the air, which have impacts on human health. The measurement was done by distinguishing the size of particle. So that, the particle with aerodynamic diameter between $2.5-10{\mu}m$ (so-called coarse particle) and aerodynamic diameter < $2.5{\mu}m$ (so-called fine particle) were considered to obtain more information about levels of the inhalable fraction of the location. The results obtained in four locations of the city of Yaound$\acute{e}$ show that the black carbon concentration is very considerable, the element sulfur is a major pollutant and the concentration of fine particle is very greater. The results obtained of fine and coarse filters range from $5-17{\mu}g/m^3$ and $10-18{\mu}g/m^3$ for the black carbon. S, Cu, Zn, Pb, Cd, As, Se and Hg are the specific findings of this work. The pollutants with a greater concentration are S, Pb, and Zn. These later seem to be non-uniformly, non-regular in some location and high compared to other countries. This work allows us to make a potential relation between pollutants and emission sources. In this framework, some suggestions have been proposed to reduce emissions for an improvement of the air quality in the environment and thus, the one of the city of Yaound$\acute{e}$.